There is conventionally known an intermediate transfer type image forming apparatus including: a support member supporting a photosensitive drum; a belt unit having a transfer belt; and a sheet conveying path extending below the belt unit. The support member is movable between an accommodated position at which the support member is accommodated in a main body casing and a withdrawn position at which the support member is withdrawn from the main body casing. When the support member is at the accommodated position, the support member is positioned above the belt unit so as to contact the transfer belt.